Part 47
At the time Morse’s Recording Telegraph was invented there were, of course, no telegraph lines in any part of the world, with the exception of the short lines of wire put up by investigators for experimental purposes. To remove the obscurity as to the purpose to be served by the telegraph was the first problem which presented itself to Morse and his backers. In 1843 an appropriation was secured of $30,000 from the U. S. Government, with which a line was built from Washington to Baltimore. This was built and operated by the Government for about two years, but the Government refused to purchase the patent rights. So the owners of the patents endeavored to get the general public interested in the telegraph as a commercial undertaking and gradually companies were founded and licensed to use the invention.
By 1851 there were as many as fifty different telegraph companies in operation in different parts of the United States. A few of these used the devices of a man named Alexander Bain, which were afterwards adjudged to infringe the Morse patents, and one or two used an instrument invented by Royal E. House of Vermont, which printed the messages received in plain Roman letters on a ribbon of paper. This at first seemed to have an advantage over that of Morse, which received the message in dots and dashes, in the Morse Code, and these had to be translated and written out by an operator before they could be delivered. However, as time went on, the operators came to read the Morse messages by the sound of the dots and dashes, instead of waiting to read the paper tape having the dots and dashes marked on it, and finally the recording feature was given up and the sounder, or instrument which simply clicks out the message, came into general use.
In the early days, the possibility of the business were little understood and many telegraph companies failed. April 8, 1851, papers were filed in Albany for the incorporation of the New York and Mississippi Valley Printing Telegraph Co. This company, which soon afterwards changed its name to Western Union, was destined to absorb the various companies throughout the country until it, in time, operated the telegraph lines over practically the entire United States, and has its blue sign in nearly every town and hamlet in the country.
[Illustration: AN EXPENSIVE EQUIPMENT NECESSARY TO-DAY
OPERATING ROOM.
In large cities like New York and Chicago, the operating rooms are very large. For instance, the main operating department of the Western Union Telegraph Co. in New York City has 1000 operators. This picture shows an operating room. The men and women sit in opposite sides of long tables. On the tables are the keys and sounders by which they send and receive the messages. Each operator has a typewriter, or “mill,” as he calls it, on which he writes off the message as it comes to him over the wire.]
[Illustration: MAIN SWITCHBOARD.
The picture shows a main switchboard in a large operating room. To this come the ends of the wires from other cities, and to it are connected the wires from the instruments in front of the operators. By putting plugs, attached to each end of a wire, into the sockets in the board, any wire can be connected with any operating position, or several local circuits can be connected up with a main line from the outside.]
[Illustration: A THOROUGH SYSTEM MUST HANDLE THE MESSAGES
A SECTION OF THE REPEATER ROOM.
When a wire runs to a distant point from the main operating department of the telegraph company in a large city, the same electric current which runs through the key of the operator as he sits at his place, busily sending messages, does not go out over the wire to that distant point. It simply goes to the repeater room and operates a repeater, which sends out another current over the long wire which leads to the destination of the message. This is necessary because the condition of the weather affects the lines and the current strength has to be changed to suit the changing line conditions. The operators haven’t time to make these adjustments, and so all the repeaters are grouped together in the repeater room where they are under the watchful eyes of experts. Here also are the delicate instruments which separate the messages coming over duplex and quadruplex wires, by responding to impulses of various strengths. These messages which have been separated are then transmitted by the duplex or quadruplex repeaters to different operators in the operating room, who hear their sounders tick out the message just the same as if it came over a simple Morse wire.]
[Illustration: CABLES ENTERING A CENTRAL OFFICE.
You may not but your father will remember the time when in large cities there were tall telegraph poles with hundreds of wires on them running along the main streets, so that the town seemed to be bound with great spiders’ web. That is all changed now, and the telegraph wires are run through ducts, placed underground. For this purpose they are made up in cables, and in the picture you see a number of cables entering a central office.]
[Illustration: THE MARVEL OF TELEGRAPH INSTRUMENTS
WHEATSTONE SENDING INSTRUMENT.
These two photographs show the most modern form of the instruments which, as we are told on another page, were invented in England by Wheatstone and Cooke. In sending a paper tape is punched in what is called a perforator, which has a keyboard like a typewriter. A certain combination of holes means a certain letter. This tape is then automatically fed through the sending instrument, which sends impulses over the wire. The tape with the holes punched through it can be seen in the picture.
On the right is the Wheatstone receiving instrument. It prints the signals received in dots and dashes on a tape, which is translated by the operator who typewrites the translation on a message blank for delivery.]
[Illustration: The automatic telegraph typewriter shown here is one of the wonderful instruments mentioned on one of the preceding pages. The operator at the other end of the line writes on a typewriter keyboard, on the sending instrument. The electric impulses are received by the machine shown above, which automatically typewrites the message on a blank, ready for delivery.]
On this page we see some of the first telegraph instruments, in fact, the very instruments which Professor Morse used in the early demonstrations of his invention. These instruments may be seen in the Smithsonian Institution at Washington, D. C. The key is known as the Vail key, because it is supposed to have been constructed by Alfred Vail, who worked with Morse in his experiments with the telegraph. As can be seen it is very simple. One wire was connected to the spring piece and the other to the post beneath it. When the key was pressed down, the contact was made and an impulse sent over the wire, either a dot, if the key was pressed down and immediately released, or a dash if it were held down for just the fraction of a second before releasing.
From the very first it was found that relays were necessary, because the current after coming a long way over the wire often was not strong enough to operate the recording instrument. Therefore, this weak current was made to go though the electro-magnets of the relay, magnetizing these and pulling to the left the upright arm which can be seen in the photograph with a little block of iron attached to it. This arm, when pulled by the magnets, made a contact at the top and allowed a strong current from a battery to flow through the magnets of the recording instrument.
The first practical recording telegraph instrument devised by Morse is shown. It looks like a clumsy affair compared to the instruments of to-day, but it worked so effectively as to convince people of the possibilities of the great invention. In the wooden box, attached to the frame at the right, is clockwork which pulled a paper tape at an even rate of speed over a pulley just beneath a needle point. This needle point is attached to a light framework having a piece of iron fastened in it. Below this iron are the electro-magnets, and when they received an impulse of current from the battery, through the relay, they pulled down the frame so that the point made a mark upon the paper tape which moved under it. Thus in the tape appeared a series of dots and dashes, which the operator, knowing the Morse Code, could easily translate into English.
[Illustration: THE FIRST TELEGRAPH INSTRUMENTS
ONE OF THE FIRST KEYS FOR SENDING TELEGRAMS.]
[Illustration: ONE OF THE FIRST RELAYS.]
[Illustration: The first recording apparatus. The box on the right contains clock work for pulling a paper tape beneath a sharp point actuated by magnets.]
[Illustration: THE LITTLE INSTRUMENTS THAT CHECK OFF THE WORDS
A LATER KEY.]
[Illustration: A LATER AND IMPROVED RECORDING INSTRUMENT.
Here we see some early telegraph instruments which have been improved somewhat from the crude devices illustrated on the preceding page. The key answers the same purpose as before, but has been improved by pivoting the lever arm, and having a coil spring, adjustable by means of a screw, so that the weight necessary to press it down can be varied to suit the likings of the operator who uses it. The play of the key or the distance it must be pressed down before it makes an electric contact, can be adjusted by another screw.
The recording instrument here shown is a much neater affair than the cumbersome device which Professor Morse first built. The cumbersome wooden box has been replaced with a neat brass frame containing the clockwork for drawing the paper tape beneath the marking point, which is attached to a piece of iron, or armature, placed just above the magnet.
Below we see the most modern types of Morse instruments. In the center is the key, which is not much changed except that it is built to be low down to a table, so that the operator may rest his forearm on the table top in front of it, and operate the key with his wrist, with less fatigue. The relay at the left is interesting. It shows how little this instrument has changed, except for refinement in its appearance, from the first relay built by Professor Morse. At the right is the Morse sounder, which has replaced the old Morse tape recording instrument. When current goes through the magnets they attract a piece of iron attached to the metal arm and pull it down to strike the brass frame. This makes a click, and when the current is intercepted, the magnets release the arm and a spring pulls it back, making another click. The operator reads the message by listening to the clicks. If the up click comes right after the down click it represents a dot. If there is a pause between them, a dash is represented.]
[Illustration:
Relay
Key
Sounder
MODERN MORSE INSTRUMENTS]
[Illustration: WHAT OCEAN CABLES LOOK LIKE WHEN CUT IN TWO
_Light Intermediate_
_Heavy Intermediate_
_Main Cable_
_Rock Cable_
_Heavy Shore End_
_Rock Cable_
_Heavy Shore End_
_Heavy Intermediate_
_Light Intermediate_
_Deep Sea_
_Bay Cable_
FIG. 1.--CABLES ON VANCOUVER-FANNING ISLAND SECTION.
Full size.
Core, 600/340.]
[Illustration:
Yarn Serving & Compound
16 No. 13 (·095) Galvanized Wires
Jute Serving
Gutta Percha
Copper Conductor
FIG. 2.--CABLES USED ON FIJI-NORFOLK ISLAND-QUEENSLAND AND NEW ZEALAND SECTIONS. Full size. Core 130/130.
This picture shows cross-sections of a cable which runs from Vancouver, B. C., to Australia and New Zealand. A cable is not laid with a uniform cross-section. On the floor of the ocean, perhaps miles below the surface, the cable rests quietly and is not moved by storms which generate great waves on the surface of the water. As the cable approaches the shore, the movement of the water goes deeper and the cable must be made heavier to prevent it from being worn by movement on the bed of the ocean. Where the cable passes over a rocky bottom, it is made much larger in diameter and is heavily armored.]
[Illustration: Here is the cable steamship “Colonia” laying the shore end of a cable. Note the row of floats upon the water which carry the cable until the end in the cable office is firmly fastened. When this is accomplished the floats are removed and the cable sinks to the bottom.]
The Story in an Ocean Cable
What is a Cable Made of?
A submarine telegraph cable as usually made consists of a core in the center of which is a strand of copper wire which varies in weight from seventy to four hundred pounds to the mile. Strands of copper wire instead of one thick wire of copper are used, because the former is more flexible. The copper conductor is covered with several coatings of rubber of equal weight to the copper wires. After this comes a coating of jute serving, then a layer of galvanized iron wires and finally a layer of yarn and compound which forms the outer covering of the cable. In addition to this where the cable lays among rocks that might injure it, chains are securely wrapped around it, so as to prevent wear and tear as much as possible.
You may not have known it, but the cable which lies on the bottom where the water is deepest is never so large as nearer the shore or in shallow water. Little by little the men who lay and look after cables have found that it is best to have a specially constructed outer covering for different depths and character of bottoms so as to provide the least possible danger of damage through the action of the water on the bottom.
How is a Cable Laid?
When the cable of sufficient length is completed, it is carried to a specially equipped vessel which has a great tank for holding the cable and the necessary machinery for lowering it over the end of the ship into the water. The cable is carefully coiled in the tank, the different coils being prevented from adhering by a coat of whitewash. First then, a sufficient length of cable is paid out to reach the cable house or shore. Here it is finally tested to see that the entire length of cable is in working order. If satisfactorily tested, the vessel steams slowly away on the course outlined, paying out the cable as she goes.
[Illustration: STORING A CABLE LONG ENOUGH TO CROSS THE OCEAN
Here we see a cable coiled round and round in the tank which holds it on board the cable ship.]
[Illustration: In the front of the picture we see the cable coming from the tank in which it is coiled. It goes over the drum of the paying-out machine and thence to the bow of the ship, where it passes over big sheaves or pulleys and down into the ocean.]
[Illustration: THE MACHINERY ON A CABLE SHIP
The paying-out machine. The cable makes a couple of turns around the big drum, which is connected to the dial, so that the dial indicates the length of cable which has been paid out into the sea.]
[Illustration: The upper forward deck of the cable steamship “Telconia,” showing the gear which is used in paying out the cable. Away in the bow are the big sheaves over which the cable goes into the sea. Nearer is a dynamometer which measures the tension on the cable.]
[Illustration: HOW THE CABLE IS DROPPED INTO THE OCEAN
Here we see the cable on the lead, as it is called, passing over the big bow sheave from which it dives into the depths of the sea.]
The vessel must pay out more than a mile of cable for every mile she travels because there must be enough slack allowed at the same time to provide for the unevenness of the bottom of the sea. For this purpose the amount of cable paid out must be measured. This is done by the paying-out machine, which is shown in one of the pictures. The difference between the speed of the ship and the amount of cable paid out gives the amount of slack. Too much slack would also be bad, so that it is a very pretty problem to pay out just enough and both the speed of the vessel and the rate of paying out the cable must be watched carefully.
One of the greatest wonders accomplished by the ingenuity of man is the ocean telegraph, by which we flash messages back and forth under the sea between the continents and completely around the world.
Hardly had the telegraph become an established fact, before Professor Morse, who made the telegraph practical, expressed the belief that a telegraph line to Europe by means of a wire laid on the bottom of the ocean was easily possible at some future time. Mr. Cyrus W. Field, the first to lay an ocean cable successfully, heard him and in his own mind said “Why not now?” The idea fixed itself so thoroughly in his resolute mind that he soon said to himself “It shall be done,” and went to work, and labored incessantly through twelve years of failure and discouragement before he accomplished his task, which was a great compliment to this giant of American stick-to-it-iveness.
While many doubted the feasibility of the project and others thought it the dream of a disordered brain, Mr. Field found many who believed in him and his idea and who loaned him their financial support for the undertaking.
[Illustration: THE CABLE ARRIVES ON THE OTHER SIDE
Landing the shore end of a cable. The cable is supported on several boats and this picture shows the inshore boat with the end of the cable reaching the beach with the seas breaking over her.]
[Illustration: THE MEN WHO MADE THE OCEAN CABLE POSSIBLE
THE PIONEERS OF THE FIRST OCEAN CABLE.]
American genius had not at that time asserted its supremacy in mechanics and so the first cable had to be made in England; so Mr. Field ordered one long enough to stretch from the west coast of Ireland to the eastern point of Newfoundland. English capitalists subscribed the money and the United States provided the vessel in which to store and from which to drop the cable into the ocean.
Upon the first attempt to lay the cable, every thing went along nicely for six days, and then suddenly the cable broke when three hundred and thirty-five miles had been laid, and many said it could not be done. Mr. Field, however, full of American pluck and determination, said “We will try again.” A second attempt was made with two ships, the U. S. S. “Niagara” and H. M. S. S. “Agamemnon.” Each ship carried half the cable and they traveled in company to the middle of the ocean. There the two pieces of the cable were spliced together and the ships started for the shores in opposite directions. Again, however, when only a little of the cable had been paid out--a little more than one hundred miles in fact--the cable broke and both ships were forced to return to England.
In his third attempt the cable was finally laid clear across the ocean and fastened at both ends. When tried it was found to work successfully and Queen Victoria and President Buchanan were able to exchange greetings upon the achievement of a wonderful work. The people celebrated the event on both sides of the ocean, but in the midst of the festivities, while a message was being flashed, something happened to the cable--what, we have never been able to learn--and the cable was silent, forever.
Nothing daunted, however, Mr. Field by his great courage induced his backers to buy him another cable and the “Great Eastern” sailed upon what was to be a most successful mission. Starting from the American side with the greatest steamship then known in charge of the previous cable, the other end was successfully landed at Hearts Content, Ireland, on July 27, 1866, in perfect working order, and the question of the ocean telegraph was solved.
[Illustration: HOW CABLES ARE REPAIRED
Here is a buoy which is anchored to the cable. The cable ship will pick it up and haul up the cable to the surface for inspection and perhaps it will have to be repaired.]
[Illustration: Three grapnels used for picking up a cable from the bed of the ocean. On the left is a common grapnel. In the middle is a special grapnel known as Trott-Kingsford. On the right is the ordinary cutting grapnel. Note the knives on the shaft and the insides of the prongs.]
[Illustration: In this picture we see a portion of a cable which has been fouled by the anchor of a ship and badly damaged. Note how the wires are bunched. The cable splicers will go to work on this and put in a new piece of cable, after which it will be let down into the sea again.]
[Illustration: The Western Union Cable ship “Minia,” fast in an ice field.]
[Illustration: POWERFUL ENGINES NEEDED ON CABLE REPAIR SHIPS
Here are the powerful engines which are used for picking up a cable which has to be raised from the bottom of the sea for inspection or repair.]
[Illustration: In this picture we see men at work splicing a cable which has been picked up out of the depths of the sea and found to be damaged.]
[Illustration: THE SHIP WHICH HELPED IN LAYING THE FIRST CABLE
ARMORING MACHINE
Here is one of the machines used for armoring the cable. By armoring is meant winding steel wires around and around the cable to protect it from being cut by sharp rocks on the bottom or by deep sea animals like the teredo, which might attack it.]
[Illustration: The “Great Eastern” which was the first ship to carry a cable across the Atlantic Ocean.]
[Illustration: This is a section of a telephone cable, known as a “bulge.” It contains inductance coils to offset what is called the condenser capacity of the cable, which would otherwise cause the talking to become blurred.]
[Illustration: THE DOTS AND DASHES WHICH FLASH ACROSS THE SEA
CONTINENTAL MORSE CODE SIGNALS USED IN CABLE WORKING]
Making repairs to a cable where it comes out of the sea on to a bold rocky shore. Note how the cable is wound with chain to protect it from the rocks.
[Illustration: Facsimile of Continental Morse Alphabet as Signalled Across the Atlantic and Copied on Tape by Siphon Recorder Instrument at the Receiving Station. Signals Enlarged for Purposes of this Illustration.
Same Signals as They Appear in Actual Working
Here are two photographs showing the continental Morse code signals used in cable working and the signals as they are received by the siphon recording instrument at the receiving station. This siphon recorder is in practical use in the cable world. The dots and dashes sent into the wire on one side of the ocean according to the Morse code, cause the siphon recorder through the means of electrified ink to make a waving line on a tape. The signals are readily reducible again if necessary to the dots and dashes of the Morse code because dots make deflections to one side of the center of the tape and dashes to the other. The operator who receives the message can therefore readily read it.
ALPHABET: